There are three different types of livestock barns commonly used for housing dairy cattle. These are normally referred to as the free-stall barn, the tie-stall barn and the pack-barn.
FIG. 1 is a floor-plan illustrating principal elements of a free-stall barn 2. As may be seen in FIG. 1, the free-stall barn 2 generally comprises one or more ranges of stalls 4, at least one feeding area 6, and a milking parlour 8.
Each range of stalls 4 typically comprises a number of stalls 10 (up to 200 or more, for example) disposed on a raised platform 12. Each stall 10 is sized to accommodate a single cow in either a standing or a lying position. Adjacent stalls 10 in the range 4 are separated by a partition 14, which is commonly composed of circular steel tube. The raised platform 12 is generally composed of a raised curb 16 which operates to separate the platform 12 from an alley 18 running along the length of the range. Mulch and bedding materials placed within the curb 16 define the platform 12, and provide a suitable material on which a cow may lay while it is in a stall 10. The curb 16 is placed so that when a cow defecates, a majority of the manure will tend to fall within the alley 18, which simplifies collection and removal of the manure from the barn 2. The alley 18 is typically formed of concrete or other impermeable surface (such as rubber mat, for example) to facilitate removal of manure and access to the stalls 10 using equipment such as a tractor.
The (or each) feeding area 6 is generally composed as an elongated manger 20. Various types of food for the cows may be placed in the manger 20, so that the cows may feed at will. Water-stations 22 are located at the end of each range of stalls 4, and are designed to permit one or more cows to drink at will. For example, in a free-stall barn designed to accommodate about 50 cows, each water station 22 may be provided as a steel trough of between 50 and 100 gallons capacity.
The milking parlour 8 is typically separated from the stall ranges 4 and feed area 6 by one or more holding pens 24 designed to accommodate one or more cows while they are waiting to enter the milking parlour 8 to be milked. Automated gates 26 may be provided to control the movement of cows through the holding pens 24 and milking parlour 8.
An important feature of the free-stall barn 2 is that the cows are free to roam about the barn, and so can enter or exit a stall 10 as they wish. Similarly, cows may freely access the feeding area 6 and so may eat and drink at will. When a cow has finished being milked, she may freely re-enter the main part of the barn, and so may eat and drink before returning to a stall 10 to lay down.
However, free-stall barns also suffer several limitations. For example, while the cows are free to roam about the barn, they must necessarily do so by walking through one or more alleys 18, which, as noted above, are typically formed of concrete or other impermeable surface. Due to the naturally high water content of cow manure, as well as the farmer's use of water for cleaning surfaces and controlling airborne dust within the barn, the alleys 18 are typically wet, and often become very slippery. These conditions promote diseases of the hooves as well as injuries to the legs and joints of the cows, leading to increased veterinary costs for the farmer and many lame cows that must be culled from the herd.
As is known in the art, following milking, a period of approximately 45 minutes is needed before the teat closes. Typically, when a cow has finished being milked, she will typically walk to the feeding area 6 to eat and drink before returning to a stall 10 to lay down. In many cases, she will lay down within a stall 10 less than 45 minutes after she has finished milking, which means that the teat has not yet closed. This exposes her to increased risk of infections of the udder, leading to further increased veterinary costs for the farmer.
Free-stall barns are typically constructed using a single standardized size of stall 10. Consequently, a relatively small cow will tend to defecate within the stall (rather than in the alley 18) and then lay down in the fresh manure, which can easily lead to diseases of the udder. Conversely, a relatively large cow will tend to hang out of the end of the stall 10 into the alley 18 where they are vulnerable to injuries due to their rear legs and udder being too close to the curb 16 and cleaning equipment in the alley 18. Furthermore, a cow can become trapped in a stall resulting in injury and possible death of the animal.
Up-keep of the bedding in the stalls 10 can be labour intensive, while suitable bedding materials (such as sawdust, wood shavings, sand and straw) can be expensive and difficult for the farmer to obtain.
In a free-stall barn many of the cows must walk long distances for food and water. Milking also requires the cows to walk long distances, and stand within the holding pen 24 for extended periods of time prior to being milked and being allowed to re-enter the main part of the barn area to eat, drink and lay down. This arrangement is not conducive for optimum dry matter intake or animal welfare.
Finally, because all the cows are feeding from a common manger 20 and drinking from a common water station 22, it is often impractical for the farmer to monitor the food and water intake of each cow. This information can be important because changes in the intake of a cow can be an early indicator of disease.
FIG. 2 is a floor-plan illustrating principal elements of a tie-stall barn 28. As may be seen in FIG. 2, the tie-stall barn 28 generally comprises one or more ranges of stalls 30, each of which includes an integrated manger 20. The manger 20 may be divided using barriers to enable the farmer to accurately monitor the dry feed intake of each cow. Each stall 10 is typically provided with an automated watering station 32, which enables the farmer to accurately monitor the water intake of each cow. Milking of the cows is accomplished while the cows are in their stalls.
The tie-stall barn is a very simple design in which the animal is tied all the time to a short chain that is bolted to a head rail within a stall. A major disadvantage of this type of housing is that the animal is confined to her stall all the time without the ability to exercise, lay down naturally or groom herself. Consequently, cows in a tie-stall get cramped and have difficulties getting up after being in the stall for a few months. Culling rates are high in this type of housing due to this reason. So-called cow trainers are used to try to keep the cow clean. The cow trainer is an electrical wire installed above the cows so that if the cow moves too far forwards she will touch the wire and receive an electrical shock. This tends to keep the cow positioned in the stall such when she defecates the majority of manure will tend to fall in the alley. Tie-stalls are labour intensive for scraping under each cow many times per day and since the cow stays in that stall all day she will use more bedding than a free-stall.
In order to alleviate this problem, it is known to install bottom mats within a tie-stall 10. These bottom mats typically need some kind of topical bedding material and they all wear and need to be replaced at a high cost. Like the free-stall, the cows get injured when they go through the front or get caught under the stall bars. Hock injuries are more common in the tie-stall barns than the free-stall barn due to the lack of room to get up. Since the cows are being milked at the same location as they lay down, the use of sprayers and misters can't be used to cool down the animals, leading to increased heat stress on the cows in the summer months. This problem also reduces feed intake and milk production. Due to animal welfare concerns many countries have moved to prohibit this type of housing for dairy cows.
FIG. 3 is a floor-plan illustrating principal elements of a pack barn 34. As may be seen in FIG. 3, the pack barn 34 generally comprises a pack area 36, a feeding area 6, a milking parlour 8, and water stations 22.
The feeding area 6, milking parlour 8 and water stations 22 are typically similar to those of the free-stall barn, and so will not be described in further detail here.
The pack area 36 of this type of barn replaces the range(s) of stalls 4 in the free-stall barn 2, and provides an area in which the cows may lie down. Typically, the pack area 36 is separated from the feeding area 6 and milking parlour 8 by a concrete wall 38 that includes one or more openings 40 permitting the free movement of cows. The pack area 36 is conventionally constructed by excavating a large hole (which may be as deep as 15 feet) which is then filled with layers of gravel, crushed stone, and sand to allow drainage of liquids. The sand layer is often covered by a layer of bedding material, which may be composed of straw, limestone, sawdust, and other bedding materials to keep the cows dry. Typically, the bedding layer of the pack area 36 must be regularly cultivated (e.g. twice each day) to keep the pack temperature correct so not to create an environment conducive to bacteria growth. Even with regular cultivation, the pack area 36 will often still become too wet, resulting in poor conditions for the cows and elevated levels of Somatic Cell Counts (SSCs) and Bacteria in the milk. In an effort to address this problem, it is common to design the size of the pack area 36 to provide a large area (e.g. as much as 23 square meters, or 250 square feet) for each cow, which is very expensive to construct and maintain. However, even with such a large pack area, problems of excess moisture are still encountered.
Depending on the porosity of the underlying soil and rock, liquids may not effectively drain from the base of the pack area 36, and so may tend to accumulate in the layers of gravel, crushed stone and sand. When this occurs, the bottom layers of the pack area 36 will eventually become saturated resulting in the necessity of excavating the saturated material and reconstructing the pack area 36 with new materials.
This type of housing tends to be very expensive to build and very labour intensive to maintain. In addition, the drainage of liquids from the lower portion of the pack area 36 and/or recurring disposal of saturated pack materials can lead to contamination of ground and surface water, and so can be harmful to the environment.
In addition, the cows must walk significant distances to obtain their water and feed, and must wait in the holding pens 24 for extended periods of time to get milked in the parlor 8.
A barn design that overcomes at least some of the above-noted problems would be highly desirable. More particularly, technical problems to be solved include: how to minimize distance that cows need to walk over wet and/or slippery floors in order to feed and be milked; how to minimize the need for cultivation of the pack area; how to minimize exposure of cows' feet and udders to excessive moisture and bacterial growth; and how to minimize detrimental environmental impacts of the dairy barn operation.
This background information is provided to reveal information believed by the applicant to be of possible relevance to the present invention. No admission is necessarily intended, nor should be construed, that any of the preceding information constitutes prior art against the present invention.